Pourable liquid, aqueous cleaning concentrates II

ABSTRACT

Pourable, liquid, aqueous cleaning concentrates comprising 
     a) at least about 10% by weight of at least one water soluble abrasive; and 
     b) from about 2 to about 30% by weight of a mixture of narrow-range alkyl polyglycol ethers, amphoteric surfactants and soap, the ratio by weight of amphoteric surfactants to narrow-range alkyl polyglycol ethers being 1:10 to 3:1, the ratio by weight of amphoteric surfactants to soap being 15:1 to 1:3 and the ratio by weight of narrow-range alkyl polyglycol ethers to soap being 25:1 and 1:1.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to pourable, liquid, aqueous cleaningconcentrates which may be used in undiluted form as scouringcompositions and in diluted form as all-purpose cleaners. Concentratesof the type in question are known and are based on the co-use ofwater-soluble abrasive components which perform a scouring function inconcentrated media, but which virtually dissolve in dilute media and,after application, can readily be removed from the substrate simply byrinsing with water.

2. Statement of Related Art

U.S. Pat. No. 4,179,414 describes stable pastes which consist of around50 to 65% by weight of sodium bicarbonate, around 50 to 35% by weight ofwater and around 5 to 20% by weight of sodium chloride and also ofaround 10 to 30% by weight of C₁₂₋₁₆ fatty acid diethanolamide, bothbased on the percentage water content, and which have a scouring effectin concentrated form and which clean hard surfaces in dilute form. Nofigures are provided as to the particle size of the sodium bicarbonate.EP 0 193 375 A2 describes liquid compositions which may contain 1.5 to30% by weight of surfactants and 6 to 45% by weight of sodiumbicarbonate with an average diameter of 10 to 500 μm. The rest consistsof water. EP 0 334 566 A2 describes aqueous compositions containing 1.5to 40% by weight of surfactants, 2.0 to 65% by weight of predominantlyundissolved potassium sulfate with the same particle size as mentionedabove, preferably 20 to 300 μm, and optionally 0.5 to 10% by weight ofsodium chloride. International patent application WO 91/08282 describesliquid scouring cleaners containing water-soluble abrasives in whicharound 1.5 to 30% by weight of surfactants, around 45 to around 75% byweight of sodium bicarbonate with a small average particle sizeof--specifically--less than 80 μm and more than 10% by weight of watermay be present. Finally, DE 42 27 863.5 describes liquid cleaningconcentrates containing water-soluble abrasives of which around 2 to 30%by weight consists of a low-foaming surfactant mixture and around 50 to65% by weight of sodium bicarbonate with an average particle size ofaround 200 μm.

Almost all known pourable, liquid, aqueous cleaners containingwater-soluble abrasive components contain a carrier phase consisting ofa combination of anionic surfactants of the sulfonate and/or sulfatetype and nonionic surfactants.

DESCRIPTION OF THE INVENTION

The problem addressed by the present invention was to provide a modern,abrasive-containing liquid cleaning composition which would meet thefollowing requirements:

good pourability for easy and exact dosing

a good abrasive cleaning effect against obstinate soil

problem-free removal, particularly of the abrasive, by rinsing

low foaming during rinsing and when used in diluted form

high ecological standard

use of dermatologically mild surfactants.

A low-foaming carrier phase made up of surfactants particularly mild tothe skin has surprisingly been found, enabling both coarse sodiumbicarbonate with an average particle size of around 200±100 μm, which isdistinguished by a particularly good abrasive cleaning effect, and alsorelatively fine sodium bicarbonate with an average particle sizedistribution of around 65±40 μm, which is distinguished by aparticularly creamy soft consistency, to be dispersed in stable form.This carrier phase consists essentially of narrow-range alkyl polyglycolethers, amphoteric surfactants and soaps.

Accordingly, the present invention relates to pourable, liquid, aqueouscleaning concentrates containing surfactants and a water-solubleabrasive which may be used in concentrated form as scouring compositionsand in dilute form as all-purpose cleaners, characterized in that theycontain

a) as water-soluble abrasive at least about 10% by weight and preferablyaround 20 to 60% by weight of sodium bicarbonate with an averageparticle size of around 20 to 500 μm and preferably of around 50 to 300μm and

b) around 2 to 30% by weight and preferably around 3 to 20% by weight ofa low-foaming surfactant mixture of narrow-range alkyl polyglycolethers, amphoteric surfactants and soap, the ratio by weight ofamphoteric surfactants to narrow-range alkyl polyglycol ethers being1:10 to 3:1, the ratio by weight of amphoteric surfactants to soap being15:1 to 1:3 and the ratio by weight of narrow-range alkyl polyglycolethers to soap being 25:1 to 1:1.

Anionic surfactants of the sulfate or sulfonate type may optionally bepresent, although the cleaning concentrates according to the inventionare preferably free from anionic surfactants of the sulfate or sulfonatetype.

The water-soluble abrasives may be selected from a large number ofinorganic salts, for example sodium sulfate, sodium carbonate, sodiumchloride, although sodium bicarbonate (hereinafter referred to in shortas bicarbonate) above all meets the requirements laid down for acommercially practicable product (cf. WO 91/8282, pages 12 et seq.).

Suitable alkyl polyglycol ethers are those with a narrow homologdistribution of the added ethylene oxide, as known from A. Behler etal., Seifen-Ole-Fette-Wachse, 116, 60-68 (1990), and from DE 38 17 415,which have a thickening effect and which are also distinguished by thefact that they are particularly mild to the skin and are readilybiodegradable. Alkyl polyglycol ethers of this type include, forexample, the narrow-range alkyl polyglycol ethers containing around 8 to18 and preferably around 9 to 16 carbon atoms in the alkyl radical andaround 2 to 8 and preferably around 2 to 5 ethylene oxide units (EO) inthe molecule. They are present in the cleaning concentrates according tothe invention in a quantity of 1 to 20% by weight and preferably 2 to15% by weight. By "narrow-range alkyl polyglycol ethers" is meant thatin a reaction between an alcohol and n moles of ethylene oxide to giveon average an ethoxylate-(EO)_(n), between 80 and 90% of the product isin the range of ethoxylate-(EO)_(n-2) to ethoxylate-(EO)_(n+2).

Mildness to the skin also applies to the amphoteric surfactants whichinclude around 0.5 to 10% by weight and preferably around 1 to 5% byweight of quaternary ammonium compounds consisting of an alkyl radicalcontaining around 7 to 18 carbon atoms and a hydrophilic head group.N-(3-N'-C₈₋₁₈ -acylaminopropyl)-N,N-dimethylammonium acetate andN-alkyl-N,N-dimethylammonium acetate are preferably used.

Nowadays, minimal foaming is essential for the acceptance of moderndomestic cleaning products. Since the combination of the nonionicsurfactants and amphoteric surfactants foams intensively, foamregulators have to be added. Soaps in quantities of around 0.05 to 5% byweight and preferably in quantities of around 0.5 to 3% by weight haveproved to be particularly effective in this regard, examples includinglinear or branched, saturated or unsaturated carboxylic acids containingaround 7 to 22 carbon atoms and preferably around 10 to 22 carbon atomsin the alkyl group and/or alkali metal, ammonium and/or alkylammoniumsalts thereof. The alkali metal salts, preferably sodium salts, and themagnesium salts of coconut oil fatty acid, isostearic acid and mixturesthereof are particularly effective.

The individual classes of surfactants in the surfactant mixture may berepresented by one or more of their compounds. As usual inoleochemistry, the alkyl polyglycol ethers may be derived from technicalalcohol mixtures of the type obtained, for example, by high-pressurehydrogenation of methyl esters based on vegetable or animal rawmaterials or by hydrogenation of aldehydes from ROELEN's oxosynthesis.

In addition to the surfactants mentioned under b), typical C₈₋₁₈ alkylpolyglycol ethers with a normal distribution of the ethylene oxideunits, for example the products commercially available as Dehydol, maybe present in a quantity of 1 to 20% by weight. In addition, C₈₋₁₈ fattyacid mono- and dialkanolamides, for example the C₈₋₁₈ fatty acidmonoethanolamide commercially available as Comperlan 100, may optionallybe present in a quantity of 0.1 to 4% by weight.

The flow properties and stability of the dispersion may be positivelyinfluenced by addition of up to 5% by weight and preferably 0.5 to 3% byweight of a polyalkylene glycol corresponding to the general formulaH-(OC(H)R¹ -CH₂)_(n) -OH, where R¹ is hydrogen or a methyl group and nis an integer of 4 to 40, and/or by addition of up to 5% by weight andpreferably 0.2 to 3% by weight of alkyl polyglycosides corresponding tothe general formula R² O-(Z)_(x), where R² is a linear or branched alkylor alkenyl group containing 6 to 22 carbon atoms, Z is a sugar unit fromthe group of aldopentoses or aldohexoses, for example glucose, mannoseand xylose, and x is on average a number of 1.3 to 1.8.

Suitable polyalkylene glycols are, for example, the polyethylene glycolswith average molecular weights of 600 and 1000 marketed under the namesof Polydiol 600 and Polydiol 1000. Suitable alkyl polyglycosides are,for example, C₈₋₁₀ alkyl polyglucosides which are marketed under thename of Plantaren 225.

In addition, preferred cleaning concentrates contain an inorganicmaterial which stabilizes the carrier phase in a quantity of 0.2 to 5%by weight and preferably in a quantity of 0.5 to 3% by weight.Stabilizing inorganic materials in the context of the invention areunderstood to be substances which contribute towards the stabilizationand viscosity regulation of the cleaning concentrates according to theinvention. The inorganic material is preferably selected from the groupof layer silicates, aluminium oxide hydrates and precipitated silicas.Suitable layer silicates are, for example, montmorillonite, calciumsilicate and magnesium silicate.

The inorganic materials surprisingly have no adverse effect on thedesired properties of the cleaning concentrates, for example readyremovability by rinsing, after use in concentrated form.

Particularly preferred cleaning concentrates contain 0.1 to 3% by weightand preferably 0.2 to 2% by weight of polymers selected from the groupof polysaccharides, modified cellulose molecules and syntheticpolycarboxylates. Suitable polysaccharides are, for example, xanthan gumor carob bean flour. Modified cellulose molecules are understood to becellulose substituted by such groups as, for example, carboxymethyl,hydroxyethyl, hydroxypropyl or methyl. Suitable syntheticpolycarboxylates are homopolymers or copolymers of acrylic acid,methacrylic acid, maleic acid or alkali metal salts thereof and C₁₋₄alkyl esters optionally crosslinked by such compounds as, for example,diallyl sucrose. The molecular weights of the polycarboxylates arepreferably above 100,000.

In addition, the concentrates according to the invention may containtypical constituents, such as inorganic or organic builders, for examplein the form of low molecular weight dicarboxylic acids or sodiumchloride, known solubilizers, such as hydrotropes and solvents,preservatives, other antimicrobial agents, dyes and fragrances.

Sodium bicarbonate forms a buffer at pH 8.7 so that the pH value of theconcentrates according to the invention is generally between 8.0 and9.0.

The cleaning compositions according to the invention are produced bymixing the individual constituents in the following order while stirringwith a commercially available blade stirrer: approximately 6% of thetotal quantity of bicarbonate is dissolved in water at around 40° C.,the fatty acid being added to the resulting solution in molten form.After the formation of a homogeneous mixture, the mixture is cooled to25° C. and the remaining constituents are subsequently added.

EXAMPLES

To demonstrate the advantages of the cleaning compositions according tothe invention, tests were carried out by the following methods:

A Brookfield RVT viscosimeter, spindle 4, 20 revolutions per minute, wasused to measure viscosity in m.Pas. The measurements were conducted at20° C.

Cleaning power was tested by the method described below which providesreadily reproducible results. The removal of soil from hard surfaces wasevaluated by the cleaning performance test described inSeifen-Ole-Fette-Wachse 112, 371 (1986).

The cleaning composition to be tested was applied to artificially soiledplastic surfaces. A mixture of soot, machine oil, triglyceride ofsaturated fatty acids and low-boiling aliphatic hydrocarbon was used asthe artificial soil for dilute application of the cleaning composition.The 26×28 cm test area was uniformly coated with 2 g of the artificialsoil using a surface spreader.

A synthetic sponge was impregnated with 10 ml of the cleaning solutionto be tested and moved mechanically over the test surface which had alsobeen coated with 10 ml of the cleaning solution to be tested. After 10wiping movements with the synthetic sponge, the cleaned test surface washeld under running water and the loose soil was removed. The cleaningeffect, i.e. the whiteness of the plastic surface thus cleaned, wasmeasured with a Dr. Lange Microcolor color difference measuringinstrument. The clean white plastic surface was used as the whitestandard. Since the Microcolor instrument was adjusted to 100% formeasurement of the clean surface and since the soiled surface produced areading of zero, the values read off for the cleaned plastic surfacesmay be equated with the percentage cleaning performance (% CP). In thefollowing tests, the CP rel. (%) values shown are the values determinedby this method for the cleaning performance of the cleaners tested,based on the cleaning performance of the cleaner used as standard(CP=100%). They represent average values of three measurements.

The foaming behavior of the concentrates according to the invention wastested as follows:

The test product was placed in a wide-necked glass beaker. Tap water wasthen run freely into the glass beaker from a height of 30 cm in thequantity designed to produce the recommended in-use solution of theproduct with the quantity of product initially introduced.

The height of foam in the glass beaker was read off immediately afteraddition of the water and also 3 minutes thereafter. The foam heightafter 3 minutes was related to the initial foam and the foam collapsewas calculated as follows: ##EQU1##

A cleaner with a foam collapse of more than 50% is defined as alow-foaming cleaner.

The quantities in the following Examples represent percentages byweight.

Examples 1 to 4

The Examples listed in Table 1 are intended to show typical ranges inwhich stable dispersions are obtained with the surfactant combinationsaccording to the invention.

Examples 5 to 8

The Examples listed in Table 2 are intended to show that a large numberof inorganic structures are suitable for improving the rheologicalbehavior of the dispersions.

Examples 9 to 12

The Examples listed in Table 3 are intended to show that the carrierphase is capable of stabilizing various quantities of sodium bicarbonateand sodium bicarbonates varying in their particle size distributions.

Examples 13 to 16

The Examples listed in Table 4 are intended to show that polymersselected from the group of polysaccharides, modified cellulose moleculesand synthetic polycarboxylates are suitable for improving therheological behavior of the dispersions.

In the following Tables,

FA=Fatty alcohol (the alkyl radicals concealed behind this need notnecessarily emanate from natural sources)

*CTFA name for the amphoteric surfactants

mTg=Average particle size distribution

NRE=Narrow range ethoxylates (ethoxylates with a narrow homologdistribution)

FSMAA=Fatty acid monoalkanolamide

MW=Molecular weight

                  TABLE 1                                                         ______________________________________                                        Ingredients/Examples                                                                       1        2        3      4                                       ______________________________________                                        C.sub.12/14 -FA-2.5 EO, NRE                                                                2.5      3.5      3.5    4                                       C.sub.12/14 -FA-4 EO                                                                       8        5        5      4                                       C.sub.10 -FA-3 EO                                                                          --       0.5      0.5    2                                       C.sub.12/18 -FSMAA                                                                         --       0.5      --     --                                      Coco Betaine*                                                                              --       --       3      --                                      Cocoamidopropyl                                                                            2.5      3        --     3                                       Betaine*                                                                      Cocofatty acid                                                                             1        1        1      1                                       Polyethylene glycol, MW                                                                    --       1        0.8    --                                      600 (Polydiol 600)                                                            Polyethylene glycol, MW                                                                    1        --       --     --                                      1000 (Polydiol 1000)                                                          C.sub.8/10 Alkyl poly-                                                                     --       --       --     0.5                                     glucoside, x = 1.6                                                            Sodium bicarbonate, 100                                                                    35       35       35     35                                      μm mTg                                                                     Perfume      0.4      0.4      0.4    0.4                                     Deionized water                                                                            ad 100   ad 100   ad 100 ad 100                                  viscosity (mPas)                                                                           5200     5800     4400   5300                                    Foam collapse (%)                                                                          100      100      96     93                                      ______________________________________                                    

                  TABLE 2                                                         ______________________________________                                        Ingredients/Examples                                                                       5        6        7      8                                       ______________________________________                                        C.sub.12/14 -FA-2.5 EO, NRE                                                                3.5      3.5      3.5    3.5                                     C.sub.12/14 -FA-4 EO                                                                       5        5        5      5                                       C.sub.12/14 -FA-6 EO                                                                       1        1        1      1                                       Cocoamidopropyl                                                                            3        3        3      3                                       Betaine*                                                                      Cocofatty acid                                                                             1        1        1      1                                       Polyethylene glycol, MW                                                                    0.5      0.5      0.5    0.5                                     600 (Polydiol 600)                                                            Sodium bicarbonate, 200                                                                    35       35       35     35                                      μm mTg                                                                     Mg Silicate, synthetic                                                                     0.8      --       --     --                                      Montmorillonite, natural                                                                   --       0.8      --     --                                      Aluminium oxide hydrate                                                                    --       --       0.8    --                                      Silica       --       --       --     0.8                                     Perfume       0.25     0.25     0.25   0.25                                   Deionized water                                                                            ad 100   ad 100   ad 100 ad 100                                  Viscosity (mPas)                                                                           4400     3650     3900   6250                                    Foam collapse (%)                                                                          88       96       100    96                                      ______________________________________                                    

                  TABLE 3                                                         ______________________________________                                        Ingredients/Examples                                                                       9        10       11     12                                      ______________________________________                                        C.sub.12/14 -FA-2.5 EO, NRE                                                                4.6      4.0      2.7    4.0                                     C.sub.12/14 -FA-4 EO                                                                       6.6      5.8      3.8    5.8                                     C.sub.12/14 -FA-6 EO                                                                       1.3       1.15     0.75  1.5                                     Cocoamidopropyl                                                                            3.9      3.5      2.3    3.5                                     Betaine*                                                                      Cocofatty acid                                                                             1.3       1.15     0.75   1.15                                   Polyethylene glycol, MW                                                                     0.65    0.6      0.4    0.6                                     600 (Polydiol 600)                                                            Sodium bicarbonate, 200                                                                    15       25       50     --                                      μm mTg                                                                     Sodium bicarbonate, 65                                                                     --       --       --     25                                      μm mTg                                                                     Mg Silicate, synthetic                                                                     0.8      0.8      0.8    0.8                                     Perfume       0.25     0.25     0.25   0.25                                   Deionized water                                                                            ad 100   ad 100   ad 100 ad 100                                  Viscosity (mPas)                                                                           2900     2900     6900   3400                                    Foam collapse (%)                                                                          93       93       72     96                                      ______________________________________                                    

                  TABLE 4                                                         ______________________________________                                        Ingredients/Examples                                                                       13       14       15     16                                      ______________________________________                                        C.sub.12/14 -FA-2.5 EO, NRE                                                                4        4        4      4                                       C.sub.12/14 -FA-4 EO                                                                       6        6        6      6                                       Cocoamidopropyl                                                                            2.5      2.5      2.5    2.5                                     Betaine*                                                                      Cocofatty acid                                                                             1        1        1      1                                       Polyethylene glycol, MW                                                                    0.8      0.8      0.8    0.8                                     600 (Polydiol 600)                                                            Methyl hydroxypropyl                                                                       1        --       --     --                                      celluose (Culminal                                                            MHPC 6000 PR)                                                                 Hydroxyethyl cellulose                                                                     --       0.3      --     --                                      (Tylose H 100.000 YP)                                                         Xanthan Gum (Rhodopol                                                                      --       --       0.8    --                                      50 MD)                                                                        Methyl methacrylate/   0.25     0.25   0.25                                   butyl acrylate copolymer                                                      (Acusol 830) --       --       --     0.5                                     Sodium bicarbonate, 100                                                                    35       35       35     35                                      μm mTG                                                                     Perfume      0.4      0.4      0.4    0.4                                     Deionized water                                                                            ad 100   ad 100   ad 100 ad 100                                  Viscosity (mPas)                                                                           4100     6400     6300   5200                                    Foam collapse (%)                                                                          100      100      100    96                                      ______________________________________                                    

We claim:
 1. A pourable, liquid, aqueous cleaning concentratecomprisinga) from about 20% to about 60% by weight of sodium bicarbonatehaving an average particle size of from about 20 to about 500 μm as awater soluble abrasive; and b) from about 2 to about 30% by weight of asurfactant mixture ofi) at least one alkyl polyglycol ether having anarrow homolog distribution of alkylene oxide, wherein 80%-90% is in arange of ethoxylate-(EO)n-2 to ethoxylate (EO)n+2, when n=2 to 8alkylene oxide groups, ii) at least one amphoteric surfactant, and iii)at least one soap, wherein the ratio by weight of component ii) tocomponent i) is from about 1:10 to about 3:1, the ratio by weight ofcomponent ii) to component iii) is from about 15:1 to about 1:3, and theratio by weight of component i) to component iii) is from about 25:1 toabout 1:1.
 2. The cleaning concentrate of claim 1 wherein from about 20to about 60% by weight of component a) is present in the concentrate. 3.The concentrate of claim 1 wherein said average particle size incomponent (a) is from about 50 to about 300 μm.
 4. The concentrate ofclaim 1 wherein component b) i) contains from 8 to 18 carbon atoms inthe alkyl group and from 2 to 8 alkylene oxide groups.
 5. Theconcentrate of claim 4 wherein said alkylene oxide groups are ethyleneoxide groups.
 6. The concentrate of claim 4 wherein component b) i)contains from 9 to 16 carbon atoms in the alkyl group and from 2 to 5alkylene oxide groups.
 7. The concentrate of claim 6 wherein saidalkylene oxide groups are ethylene oxide groups.
 8. The concentrate ofclaim 1 wherein component b) is present in from about 2 to about 20% byweight.
 9. The concentrate of claim 1 wherein component b) ii) is atleast one of N-(3-N'-acylaminopropyl)-N, N-dimethylammonium acetate inwhich the acyl group contains from 8 to 18 carbon atoms, and N-alkyl-N,N-dimethylammonium acetate in which the alkyl group contains from 8 to18 carbon atoms.
 10. The concentrate of claim 1 wherein component b)iii) is at least one carboxylic acid wherein the acid may be completelyor partially present in salt form and the alkyl group therein containsfrom 7 to 22 carbon atoms.
 11. The concentrate of claim 10 wherein inthe at least one carboxylic acid the alkyl group contains from 10 to 22carbon atoms.
 12. The concentrate of claim 1 which additionallycomprises up to about 5% by weight of a polyalkylene glycolcorresponding to the formula H-(OC(H)R¹ -CH₂)_(n) -OH, in which R¹ ishydrogen or a methyl group and n is an integer of 4 to
 40. 13. Theconcentrate of claim 1 which additionally comprises up to about 5% byweight of an alkyl polyglycoside corresponding to the formula R²O-(Z)_(x), in which R² is a linear or branched alkyl or alkenyl groupcontaining 6 to 22 carbon atoms, Z is a sugar unit from the group ofaldopentoses or aldohexoses, and x is on average a number of 1.3 to 1.8.14. The concentrate of claim 1 which contains from about 0.2 to about 5%by weight of an inorganic carrier phase stabilizing agent selected fromthe group consisting of layer silicates, aluminum oxide hydrates andprecipitated silicas.
 15. The concentrate of claim 1 which additionallycomprises from about 0.1 to about 3% by weight of a polymer selectedfrom the group consisting of polysaccharides, modified cellulosemolecules, and synthetic polycarboxylates.
 16. The concentrate of claim2 wherein component a) is an inorganic salt;component (b) i) containsfrom 8 to 18 carbon atoms in the alkyl group and from 2 to 8 ethyleneoxide groups; component b) is present in from about 3 to about 20% byweight; and component b) iii) is at least one carboxylic acid whereinthe acid may be completely or partially present in salt form and thealkyl group therein contains from 7 to 22 carbon atoms.